Chart width. Default is 38, so both the chart and the battery indicator fit the tmux status line. Higher values may require disabling the battery indicator or raising the status-right-length value in ~/.tmux.conf.

--datfile FILENAME

Specify the file to log CPU stats to. Default: $HOME/.rainbarf.dat

--skip NUMBER

Do not write CPU stats if file already exists and is newer than this many seconds. Useful if you refresh tmux status quite frequently.

CAVEAT

Time remaining

If the --remaining option is present but you do not see the time in your status bar, you may need to increase the value of status-right-length to 48.

Color scheme

If you only see the memory usage bars but no CPU utilization chart, that's because your terminal's color scheme need an explicit distinction between foreground and background colors. For instance, "red on red background" will be displayed as a red block on such terminals. Thus, you may need the ANSI bright attribute for greater contrast, or maybe consider switching to the 256-color palette. There are some issues with that, though:

Other color schemes (notably, solarized) have different meaning for the ANSI bright attribute. So using it will result in a quite psychedelic appearance. 256-color pallette, activated by the --rgb flag, is unaffected by that.

The older versions of Term::ANSIColor dependency do not recognize bright/RGB settings, falling back to the default behavior (plain 16 colors). However, the whole Term::ANSIColor is optional, it is only required to preview the effects of the "OPTIONS" via command line before actually editing the ~/.tmux.conf. That is, rainbarf --bright --tmuxis guaranteed to work despite the outdated Term::ANSIColor!

Another option is skipping the system colors altogether and use the RGB palette (rainbarf --rgb). This fixes the issue 1, but doesn't affect the issue 2. It still looks better, though.

Persistent storage

CPU utilization stats are persistently stored in the ~/.rainbarf.dat file. Every rainbarf execution will update and rotate that file. Since tmux calls rainbarf periodically (every 15 seconds, by default), the chart will display CPU utilization for the last ~9.5 minutes (15 * 38). Thus, several tmux instances running simultaneously for the same user will result in a faster chart scrolling.